Unable to connect (iptables problem?)

Ok, after a few tries (and forgotten dependencies) I successfully finished the ISPConfig installation after performing a "Perfect Setup" on my remote dedicated server (running FC4).

My problem now is that I am unable to connect to my server via http or https (referencing the IP address directly). I chose SSL and port 81 for ISPConfig during the installation.

I dont think this is an ISPConfig-only problem as I am unable to connect to my normal Apache server via port 80 either. Could this be a problem in my iptables? I'm relatively new to linux so I dont want to screw up this table by just messing around with it.